using MCVIngenieros.Healthchecks.__;
using MCVIngenieros.Healthchecks.__.__Controllers;
using MCVIngenieros.Healthchecks.Abstracts;
using MCVIngenieros.Healthchecks.Options;
using Microsoft.Extensions.DependencyInjection.Extensions;
using Microsoft.Extensions.Options;
using System.Reflection;

namespace MCVIngenieros.Healthchecks;

// Extension methods for IServiceCollection
public static class HealthCheckServiceCollectionExtensions
{
    private static IServiceCollection AddHealthChecksSupport(this IServiceCollection services, HealthCheckContainerOptions options)
    {
        ArgumentNullException.ThrowIfNull(services, nameof(services));
        services.AddSingleton<IHealthCheckContainer, HealthCheckContainer>();
        services.AddSingleton(Microsoft.Extensions.Options.Options.Create(options));
        services.AddCheck<ImAliveHealthcheck>();
        services.AddControllers().AddApplicationPart(typeof(HealthCheckController).Assembly);
        return services;
    }

    public static IServiceCollection AddHealthChecksSupport(this IServiceCollection services)
    {
        ArgumentNullException.ThrowIfNull(services, nameof(services));
        var options = new HealthCheckContainerOptions();

        var scope = services.BuildServiceProvider().CreateScope();
        var config = scope.ServiceProvider.GetRequiredService<IConfiguration>();
        scope.Dispose();
        services.Configure<HealthCheckOptions>(nameof(HealthCheckOptions), config.GetSection(nameof(HealthChecksConfigs)));
        scope = services.BuildServiceProvider().CreateScope();
        var hcopts = scope.ServiceProvider
            .GetRequiredService<IOptionsSnapshot<HealthCheckOptions>>().Get(nameof(HealthCheckOptions));
        scope.Dispose();

        if (!string.IsNullOrWhiteSpace(hcopts.CacheDuration) && TimeSpan.TryParse(hcopts.CacheDuration, out TimeSpan cacheDuration))
        {
            options.CacheDuration = cacheDuration;
        }

        if (!string.IsNullOrWhiteSpace(hcopts.Timeout) && TimeSpan.TryParse(hcopts.Timeout, out TimeSpan timeout))
        {
            options.Timeout = timeout;
        }

        if (hcopts.AssembliesToScan != null && hcopts.AssembliesToScan.Length > 0)
        {
            options.AssembliesToScan = hcopts.AssembliesToScan.Select(Assembly.Load);
        }

        return services.AddHealthChecksSupport(options);
    }

    public static IServiceCollection AddHealthChecksSupport(this IServiceCollection services, Action<HealthCheckContainerOptions>? configure = null)
    {
        ArgumentNullException.ThrowIfNull(services, nameof(services));
        ArgumentNullException.ThrowIfNull(configure, nameof(configure));
        var options = new HealthCheckContainerOptions();
        configure?.Invoke(options);
        return services.AddHealthChecksSupport(options);
    }

    public static IServiceCollection AddHealthCheck<T>(this IServiceCollection services)
        where T : class, IHealthCheck
        => services.AddCheck<T>();

    public static IServiceCollection AddCheck<T>(this IServiceCollection services)
        where T : class, IHealthCheck
    {
        services.TryAddTransient<IHealthCheck, T>();
        return services;
    }

    public static IServiceCollection DiscoverHealthChecks(this IServiceCollection services)
    {
        // This will trigger the discovery when the container is built
        var provider = services.BuildServiceProvider();
        var container = provider.GetRequiredService<IHealthCheckContainer>();
        container.DiscoverHealthChecks();
        return services;
    }
}